In my prior patent application U.S. Ser. No. 166842, filed July 8, 1980, now U.S. Pat. No. 4,355,639 "Apparatus for the Parenteral Administration of Liquids at a Constant, Adjustable Flow Rate", there is described an apparatus for accurately controlled administration of parenteral fluid, which is suitable for use with glass as well as with limp bottles, and which maintains the flow rate essentially constant throughout the period of time taken to empty the liquid container.
Some readjustment is desirable if the container is of the collapsing kind if the flow rate is to be maintained with extreme accuracy. The apparatus in accordance with the aforementioned application, now U.S. Pat. No. 4,355,639 uses a flow stabilization device which includes a body formed with a cavity therein to which a tubular inlet connects with the bottom of a dripping tube or funnel, an outlet passage is provided adapted for connection to a cannula for administration of liquid to a patient, and a flexible membrane, removably covering the opening of the outlet passage seals off the communication path between the inlet and the outlet, the other side of the membrane being exposed to ambient air.